Effect of weld heat input on toughness and structure of HAZ of a new super-high strength steel

Bulletin of Materials Science

关键词: Super-high strength steel;    heat-affected zone;    fracture;    fine structure.;   

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

Fracture morphology and fine structure in the heat-affected zone (HAZ) of HQ130 super-high strength steel are studied by means of SEM, TEM and electron diffraction technique. Test results indicated that the structure of HAZ of HQ130 steel was mainly lath martensite (ML), in which there were a lot of dislocations in the sub-structure inside ML lath, the dislocation density was about (0.3 ∼ 0.9) × 1012/cm2. No obvious twin was observed in the HAZ under the condition of normal weld heat input. By controlling weld heat input ($E \leq$ 20 kJ/cm), the impact toughness in the HAZ can be assured.

【 授权许可】

CC BY